Compostable plastic for thermoforming and injection moulding

Two new variants have been added by Basf to its range of compostable and partially bio-based plastic ecovio.
Thermoformed trays and cups can now be made with ecovio T2308. This plastic exhibits similar mechanical properties to those of amorphous PET, but it differs from this conventional thermoforming material by virtue of its compostability and its high content of renewable resources (polylactic acid). The content of ecoflex, which is Basf's compostable polyester, accounts for the fact that the material is not too stiff or too brittle. As a result, thermoformed trays and cups are not damaged during transportation and storage. The ecoflex component also ensures a balanced stiffness-to-strength ratio and sufficient low-temperature impact strength. The processing window for ecovio T, between 80 and 120°C, is very broad in comparison to other plastics. Processing can be carried out on conventional flat-film installations and at the processing speeds that are typical for thermoforming. Like all ecovio grades, it also complies with the stipulations for products that come into contact with food. The material is translucent and can be adequately sealed with cover films.
The second novelty in the ecovio product line, namely, the injection-molding grade ecovio IS1335, also offers good stiffness. It can be processed using single-cavity or multi-cavity moulds that are equipped with or without hot runners. This material exhibits moderate flowing characteristics and is dimensionally stable under heat up to 55°C. This variant lends itself for thin-walled, complex and high-quality packaging, which should preferably be manufactured by injection molding and should be compostable. With an eye towards differentiating the product on the market, the product can also be decorated employing in-mold labeling. In cooperation with independent institutes, Basf has conducted experiments on the compostability of injection moulded test specimens. Results show that, depending on the application, injection moulded products made of ecovio IS1335 having wall thicknesses of as much as 1.1 mm degrade in accordance with the EN 13432 standard for compostable packaging.